Towel bar



FIG. 1 is a perspective view of a towel bar showing my new design;

FIG. 2 is a top plan view thereof, the bottom plan view being a mirror image;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof; and,

FIG. 5 is a right side elevation view thereof, the left side elevation view being a mirror image.

The broken lines show portions of the design that form no part of the claimed design. 

CLAIM The ornamental design for a towel bar, as shown and described. 